Industrial robots have hitherto been introduced into production lines of factories, contributing to improvement in production efficiency. The industrial robots are excellent in the function of gripping objects such as parts and articles conveyed in one line and transferring the objects to another line accurately any number of times.
To grip the objects, air-chuck and multi-fingered robot hands are used in the industrial robots.
The objects to be gripped by such a robot hand include various objects such as heavy objects, light objects, large objects, small objects, minute objects, hard materials, soft materials, fragile objects, rigid objects, or mixed or variable objects thereof. Therefore, many materials, shapes, dimensions, properties etc. are devised for a surface of a robot gripping portion of a robot hand, which significantly affects the gripping performance.
For example, it is proposed to fabricate the robot gripping portion from a soft material such as rubber and resin, and control an operation by mounting a sensing component such as a sensor (Patent Document 1), to dispose a material having a large friction coefficient on a surface or make the surface uneven (Patent Document 2), to cover a surface with an elastic material (Patent Document 3), etc., and measures are taken to enhance the gripping performance from material, physical, and chemical viewpoints.
Therefore, if a type of objects to be gripped is fixed as in the case of an industrial robot hand used in an assembling production line or a robot hand performing only a certain operation, the gripping performance can be improved by taking measures for optimizing a material etc. depending on the objects to optimize the tackiness and the friction coefficient of the gripping portion surface.